Self-closing sealable valve bag

ABSTRACT

A valve bag comprising: a bag body; a valve passage formed in the bag body; and a sealable valve sleeve secured within the valve passage, an exterior portion of the valve sleeve extending along an adjacent portion of the bag body, the exterior portion of the valve sleeve being unsecured to the adjacent portion of the bag body.

BACKGROUND OF THE INVENTION

This invention relates generally to valve bags, and more particularly to valve sleeves used in valve bags for granular products, such as animal feed, animal supplements, grains, and fertilizers.

Flexible bags such as paper shipping sacks may include sealable sleeves placed in the filling valves. A sealable sleeve provides a convenient means to securely close the flexible bag to prevent the contents of the bag from leaking or sifting out of the bag. Sleeves may be constructed of polyethylene tubing or of paper, for example.

A typical paper sleeve for a paper shipping sack (such as a pasted valve type multi-wall shipping sack) is made from a rectangular sheet of kraft paper that is rolled into a cylindrical shape and secured in the cylindrical shape by overlapping and gluing opposing edges of the sheet of paper to one another, forming a lapped seam. Such a sleeve is typically mounted to an opening, called a valve or filling aperture, located in a corner of the bag, that is used to allow introduction of the product that is to be held within the bag. This arrangement has been used even in more advanced shipping sacks that include a thermoplastic film liner adhered to the inner surface of the sleeve valve. In order to seal the paper sleeve and therefore the valve or filling aperture after the shipping sack is full, heat is applied to the thermoplastic film liner near an exterior end of the sleeve valve to secure the contents within the shipping sack. Sealing is typically accomplished using conduction heating, pressure, microwave energy, or ultrasonic application.

The trend in manufacturing processes now, however, particularly with extended valve tube bags, is not to provide one sealing apparatus per packing apparatus, since it requires less capital expense to use only one or two sealing apparatus for a packaging line, and the line speed can also be increased if common sealing apparatus are used for all the packing apparatus. The difficulty lies in that the filled, but unclosed and unsealed bags must be transported by conveyer to the sealing apparatus location. The bags may typically be dropped onto a conveyer.

Due to the stiffness of the valve tube material, the valve tube tends to remain open somewhat, as the bag is dropped onto the conveyer, leading to unacceptable spillage and dusting. In addition, the operation of the sealing apparatus may require that the bag be tipped from an upright position, to a position on its side, further leading to the possibility of dusting and spillage.

The foregoing illustrates limitations known to exist in present valve bags. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth-above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.

SUMMARY OF THE INVENTION

In one aspect of the present invention, this is accomplished by providing a valve bag comprising: a bag body; a valve passage formed in the bag body; and a sealable valve sleeve secured within the valve passage, an exterior portion of the valve sleeve extending along an adjacent portion of the bag body, the exterior portion of the valve sleeve being unsecured to the adjacent portion of the bag body.

The foregoing and other aspects will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawing figures.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

FIG. 1 shows an unfilled self-closing sealable valve bag according to the present invention; and

FIG. 2 is a cross-sectional side view of a portion of the valve bag shown in FIG. 1 showing details of the valve.

DETAILED DESCRIPTION

FIG. 1 shows a self-closing sealable valve bag 10 with a top 12 and bottom 14. A self-closing valve 16 is positioned between overlapping flaps 20, 22 (See FIG. 2), typically in the top 12 of the bag 10.

As shown in FIG. 2, the top 12 of bag 10 is formed by at least partially overlapping inner flap 20 and outer flap 22. A valve passage 18 is formed between the overlapping flaps 20, 22.

Valve (or valve sleeve) 16 is positioned within the valve passage 18 and is secured (as described below) to the inner and outer flaps 20, 22. Valve 16 consists of a tubular valve liner 24, which is preferably formed from a polymeric material such as polyethylene, with an upper valve support 26 and a lower valve support 28 secured to the valve liner 24. Typically, valve supports 26, 28 are formed from kraft paper and are separate flat pieces of the kraft paper.

An exterior portion 30 of the valve sleeve 16 extends laterally beyond the end of outer flap 22. The exterior portion 30 of valve sleeve 16 is not secured to inner flap 20 (shown at 50). This allows the unsecured exterior portion 30 to be rotated upward after bag 10 is filled so that both sides of this exterior portion 30 are accessible by a sealing device. Depending upon the material used for the valve liner 24, pressure and/or heat is applied to the exterior portion 30 to seal the valve 16 closed. Other means, not shown, can be used to seal the valve closed, such as adhesives, deformable closure systems, similar to those commercially available under the trademark Ziploc®, etc.

Preferably, the inner end 32 of the upper valve support 26 extends interiorly beyond the valve liner inner end 38. Also, preferably, the inner end 34 of the lower valve support extends to the valve liner inner end 38. The interior portion of the valve sleeve 16 is secured to and only partially supported by the inner flap 20. At least a portion (the right most portion shown in FIG. 2) is not secured to and is unsupported by the inner flap 20. Preferably, the inner end 42 of the inner flap extends below and is unsecured to the lower valve support 28.

In one embodiment, the valve sleeve 16 has a first or exterior end 30 that remains unsecured to the adjacent portion of the inner flap 20, a middle portion 36 that is secured to the inner flap 20, and a second end portion (the right most portion shown in FIG. 2) that is unsecured and unsupported by the inner flap 20.

During filling, material flows into bag 10 through valve passage 18 in valve sleeve 16. As the material approaches the top 12 of bag 10, the material will fill the area between the inner end 42 of the inner flap and the lower valve support 28 causing the valve sleeve 16 to collapse and close the valve passage 18. This allows temporary handling of the filled bag until the exterior portion 30 of valve 16 can be permanently sealed closed. 

1. A valve bag comprising: a bag body; a valve passage formed in the bag body; and a sealable valve sleeve secured within the valve passage, an exterior portion of the valve sleeve extending along an adjacent portion of the bag body, the exterior portion of the valve sleeve being unsecured to the adjacent portion of the bag body.
 2. The valve bag according to claim 1, wherein the valve sleeve comprises an upper valve support having an inner end, a lower valve support having an inner end, and a valve liner having an inner end, the upper valve support inner end extending beyond the valve liner inner end.
 3. The valve bag according to claim 1, wherein the valve sleeve comprises an upper valve support having an inner end, a lower valve support having an inner end, and a valve liner having an inner end, the lower valve support inner end extending to about the valve liner inner end.
 4. The valve bag according to claim 1, wherein the valve sleeve comprises an upper valve support having an inner end, a lower valve support having an inner end, and a valve liner having an inner end, the upper valve support inner end extending beyond the valve liner inner end, the lower valve support inner end extending to about the valve liner inner end.
 5. The valve bag according to claim 2, wherein the bag body comprises an inner flap and an outer flap, the inner flap and the outer flap partially overlapping forming the valve passage.
 6. The valve bag according to claim 5, wherein the inner flap has an inner end, an inner end of the valve sleeve extending beyond the inner flap inner end.
 7. The valve bag according to claim 6, wherein a first portion of the inner flap is attached to a first portion of the lower valve support, and a second portion of the inner flap, extending interiorly from the first portion of the inner flap, is unattached to the lower valve support.
 8. The valve bag according to claim 2, wherein the valve liner is a tubular sleeve having open ends.
 9. A method of sealing the valve bag according to claim 1, comprising: after filling the valve bag, rotating the unsecured exterior portion of the valve sleeve to permit access to opposite exterior surfaces of the valve sleeve; and applying force to the opposite exterior surfaces of the valve sleeve sealing the valve sleeve.
 10. The method according to claim 9, further comprising: applying heat to the opposite exterior surfaces of the valve sleeve.
 11. A valve bag comprising: a bag body having an inner flap and an outer flap, the inner flap and the outer flap at least partially overlapping; a valve passage formed between the overlapping inner and outer flaps; and a sealable valve sleeve secured to the inner and outer flaps, the valve sleeve having a first end portion extending exteriorly beyond an end of the outer flap, the valve sleeve first end portion being unsecured to an adjacent portion of the inner flap.
 12. The valve bag according to claim 11, wherein the valve sleeve has a second end portion extending interiorly beyond an end of the inner flap.
 13. The valve bag according to claim 12, wherein the valve sleeve second end portion is secured to the outer flap.
 14. The valve bag according to claim 12, wherein the valve sleeve second end portion is unsecured to an adjacent portion of the inner flap.
 15. A method of sealing the valve bag according to claim 11, comprising: after filling the valve bag, rotating the first end portion of the valve sleeve to permit access to opposite exterior surfaces of the valve sleeve; and applying force to the opposite exterior surfaces of the valve sleeve first end portion sealing the valve sleeve.
 16. A valve bag comprising: a bag body having an inner flap and an outer flap, the inner flap and the outer flap at least partially overlapping; a valve passage formed between the overlapping inner and outer flaps; and a sealable valve sleeve secured to the inner and outer flaps, the valve sleeve comprising a tubular sleeve having an upper valve support secured to an upper portion thereof and a separate lower valve support secured to a lower portion thereof, the valve sleeve having: a first end portion extending exteriorly beyond an end of the outer flap, a second end portion extending interiorly beyond an end of the inner flap and a middle portion between the first end portion and the second end portion, the valve sleeve first end portion being unsecured to an adjacent portion of the inner flap, the valve sleeve middle portion being secured to both the outer flap and the inner flap, the valve sleeve second end portion being secured to an adjacent portion of the outer flap and being unsecured to the inner flap.
 17. A method of sealing the valve bag according to claim 16, comprising: after filling the valve bag, rotating the first end portion of the valve sleeve away from the adjacent portion of the inner flap allowing access to the exterior surfaces of the upper valve support and the lower valve support; and applying at least one of force and heat to the exterior surfaces of the upper valve support and the lower valve support sealing the valve sleeve. 